1. Field of the Invention
The present invention relates to a secondary battery, and more particularly, to a protection circuit module and a secondary battery including the same.
2. Description of the Related Art
In recent years, due to rapid development of electronics, communications, and computer industries, portable electronic devices are being widely used. Meanwhile, rechargeable secondary batteries are being mainly used as power sources of portable electronic devices.
Currently, pack type batteries are being widely used as secondary batteries. A pack type battery is a unit in which a bare cell providing electric energy and a protection circuit module (PCM) controlling charge and discharge of the bare cell are integrated. The protection circuit module includes a circuit board to which various circuit devices are mounted. The protection circuit module is coupled to the bare cell by laser welding an electrode tab formed in the circuit board to the bare cell whereby the circuit board and the bare cell are physically and electrically connected to each other. However, the protection circuit module can be separated from the bare cell at the welded portion by an external impact, so it is necessary to improve the welding structure of the protection circuit module.